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» Film-Tech Forum ARCHIVE   » Operations   » Film Handlers' Forum   » Microswitch-controlled Brains (Page 1)

 
This topic comprises 2 pages: 1  2 
 
Author Topic: Microswitch-controlled Brains
Joe Redifer
You need a beating today

Posts: 12859
From: Denver, Colorado
Registered: May 99


 - posted 08-10-2008 02:19 AM      Profile for Joe Redifer   Author's Homepage   Email Joe Redifer   Send New Private Message       Edit/Delete Post 
Any big fans of microswitch brains here on the forum? Anyone?

I hate 'em! I installed a bunch o' phase control Strong platters in the theater that I am at now many years ago (make and model of platter was NOT my choice, but anything was better than the ORCs we had). They worked pretty well considering that they are Strong platters and are therefore purposely designed to suck ass. But as you know, the LEDs in phase control brains wear out after 4 or 5 years or so and must be replaced. This happened before I returned to this location. When they did start to wear out, the manager at the time (who is also a registered sex offender and was stealing from the company in many ways) ordered the microswitch conversion kit. Only a registered sex offender would be this retarded. He was fired for extreme stupidity.

Usually they work OK, but some times they stick ON or OFF in the middle of a show FOR NO REASON (other than that they are STRONG). This causes the "tension-safe" on the platter to engage and shut off power. The projector keeps pulling film happily through even though the film is piling up on the floor. That is because we use the shitty FP-350 Optical failsafes or whatever they are called (any fans of this failsafe??? Anyone???). The film dumps down and the failsafe doesn't care. Since the payout deck is controlled by the take-up variac (who thought of this idea originally? I bet he was an asshole) the film is wrapping like a mofo on crack. Since Strong brains were designed by people with Down Syndrome™ and have a bunch of little rollers around them, you can get really thick wraps on the order of multiple inches. Eventually the failsafe will decide enough is enough and stop the projector, but not until the film is literally tied into knots inside the brain.

NOTE: This always happens when the guy who rents our theaters for Bollywood movies is telling me what trailers must go on his crappy film and in what order. This trailer is attached to the start of reel 1, the next trailer is attached to the start of reel 5, etc. He also complains to me that the auditorium he is in is too small, like I have anything to do with that or even give a rat's ass. I just nod and walk away.

MORAL OF STORY: Microswitch brains suck. The designers who work at Strong suck even more... or at least the ones who worked there in the past. Change the design for cryin' out loud! Oh, and the FP-350 failsafes also suck.

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Jeremy M Smith
Film Handler

Posts: 48
From: Taupo New Zealand
Registered: Aug 2008


 - posted 08-10-2008 02:42 AM      Profile for Jeremy M Smith   Email Jeremy M Smith   Send New Private Message       Edit/Delete Post 
We have the FP-350 in 2 of our 5 cinema and half of our brains are microswitch's. I hate the FP-350 sometimes if you are not careful they will register that there is no film when you start a show and stop the projector. the other 3 cinema I installed relays in the veriac it self witch work much better and installed a different cue sensor (can't remember the make or model)but I have never had a problem really with the microswitchs but at one point I had to replace most of them. but I could get them from a electronic shop witch was great as it takes about 2 - 3 months to get anything from strong since im in new Zealand

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Joe Redifer
You need a beating today

Posts: 12859
From: Denver, Colorado
Registered: May 99


 - posted 08-10-2008 02:49 AM      Profile for Joe Redifer   Author's Homepage   Email Joe Redifer   Send New Private Message       Edit/Delete Post 
Why did you have to replace your microswitches if you've never had any problems with them?

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Jeremy M Smith
Film Handler

Posts: 48
From: Taupo New Zealand
Registered: Aug 2008


 - posted 08-10-2008 02:52 AM      Profile for Jeremy M Smith   Email Jeremy M Smith   Send New Private Message       Edit/Delete Post 
I had some projectionest complain that they where not working. but every time I used them they where fine so I just went ahead and replaced them anyway. but funny enough they still compained.

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Joe Redifer
You need a beating today

Posts: 12859
From: Denver, Colorado
Registered: May 99


 - posted 08-10-2008 03:01 AM      Profile for Joe Redifer   Author's Homepage   Email Joe Redifer   Send New Private Message       Edit/Delete Post 
I agree that it is difficult to replicate the problems. It is so random.

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Monte L Fullmer
Film God

Posts: 8367
From: Nampa, Idaho, USA
Registered: Nov 2004


 - posted 08-10-2008 03:30 AM      Profile for Monte L Fullmer   Email Monte L Fullmer   Send New Private Message       Edit/Delete Post 
Agree. Microswitch brains DO suck! Had two brains run wild on me in one night (major backwraps) .. and I had replaced these switches less than a year ago.

You get booth clowns that pull the ring out on an angle and with a microswitch brain and that filmroll not centered, a good case of thrown prints towards the end of the presentation is apparent due to the 'off and on' action of the brain.

But unfortunately, when theatre owners rather go cheap and use micros instead of spending the extra for phase controls, you pay what you pay for.

..Yet, I've got 4 phase controlled brains that I converted back from the micros and they've been working great for over 4 yrs now.

Platter decks are made to turn on a continual motion, not to be shut off and turned on all the time - why I love the AW3(R) platters.

[Confused] oh well ...

Only prob I have with FP-350's is that one of the wires that is attached to the terminal strip at the end loves to break loose for some odd reason, causing the automation not to function. Otherwise, with routine wiping underneath to clean the sensors, they've been a pretty dependable failsafe unit.

..and it does help if you change out your cues from time to time since they do wear out. Plus, it all depends HOW you're putting the cuetape on for the FP-350 to sense: You take a half-in strip of cue tape and wrap it around the edge of the film soundtrack side inbetween the sprocketholes.

-Monte

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Jaime Tuzzio
Film Handler

Posts: 50
From: Salem, OR, USA
Registered: Apr 2008


 - posted 08-10-2008 03:40 AM      Profile for Jaime Tuzzio         Edit/Delete Post 
Oh, that just brought back some fantastic memories.

The only time I ever had a microswitch brain suddenly stick ON or OFF (usually ON) in the middle of a show was when the switch needed calibrated or changed. My only unexplained random brain issues have been with the SCDC platter system. Fortunately, 98% of the time whatever the problem is starts up right at show start, so I'm immediately aware of it and can usually fix it without stopping the show.

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Joe Redifer
You need a beating today

Posts: 12859
From: Denver, Colorado
Registered: May 99


 - posted 08-10-2008 03:41 AM      Profile for Joe Redifer   Author's Homepage   Email Joe Redifer   Send New Private Message       Edit/Delete Post 
One of the very few things I like about the Strong platter is I can lift the ring straight up without collapsing it and the print doesn't move, not even the leader. The ring comes out as easily as the brain. Takes two hands, but what do I know? Regardless, the prints stay centered... at least on my shifts.

I have tried cleaning the bottom of the FP-350s and they read cues fine but I think the issue may be more of the film falling down where the failsafe isn't looking due to poor design.

Would microswitch brains cause extra wear on a platter motor? I need all of the ammo I can get when trying to order phase control conversion kits which I will surely be denied. I have such a hard time getting anything it is ridiculous.

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Frank Angel
Film God

Posts: 5305
From: Brooklyn NY USA
Registered: Dec 1999


 - posted 08-10-2008 04:45 AM      Profile for Frank Angel   Author's Homepage   Email Frank Angel   Send New Private Message       Edit/Delete Post 
I have a boss who's got a microswitch-controlled brain.

Baud-ump-bump.

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Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99


 - posted 08-10-2008 10:37 AM      Profile for Mark Gulbrandsen   Email Mark Gulbrandsen   Send New Private Message       Edit/Delete Post 
quote: Joe Redifer
Usually they work OK, but some times they stick ON or OFF in the middle of a show FOR NO REASON (other than that they are STRONG).
I service more locations with microswitch Alphas than any other kinda platter and they rarely if ever give any trouble. If the switches are replaced every two years as they are supposed to be(as per Bob Potts) then 99% of the time they give no problem at all. Also, you have to use the correct microswitch... use of the wrong one will definately lead to problems as well as poor pay out performance. Also, Honeywell makes the switches, not Wrong International. Make sure the switch clicks right in the center of the P.O. arm swing.

FWIW: The drive motors used on these platters are not stable enough to be able to use a linear feed control device like the phase control. They may work now but they will come back to haunt you in the near future!

Mark

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Louis Belloisy
Expert Film Handler

Posts: 120
From: morris, ct usa
Registered: Jun 2006


 - posted 08-10-2008 11:26 AM      Profile for Louis Belloisy   Author's Homepage   Email Louis Belloisy   Send New Private Message       Edit/Delete Post 
Our little theater is equipped with 6 Potts platters and they are all micro switch controlled. Back a few years ago the owner converted one platter (3 disc's) to optical and they have all eventually failed. I just replaced the optical device with a micro-switch. Once in a blue moon, one will stick and cause a brain wrap, a little burst of WD-40 will clear it up. Once every few months i give each switch a little lube with with the WD-40 and really not have had a problem.

Louis

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Jeremy Weigel
Phenomenal Film Handler

Posts: 1062
From: Edmond, OK, USA
Registered: Mar 2007


 - posted 08-10-2008 04:23 PM      Profile for Jeremy Weigel   Email Jeremy Weigel   Send New Private Message       Edit/Delete Post 
Converted all 6 of our Strong platters from carbon switches to micro-switches 15 years ago and haven't had a switch go bad or a thrown print.

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Troy Hilsman Powell
Film Handler

Posts: 30
From: Jacksonville,FL
Registered: May 2007


 - posted 08-10-2008 05:02 PM      Profile for Troy Hilsman Powell   Email Troy Hilsman Powell   Send New Private Message       Edit/Delete Post 
Here is a trick that has always worked for me.Go to radio shack and pick up some caps,one for each brain and wire the cap across the switch.Radio shack skew number is 272-1055.This will stop the arcing across the contacts in the switch hence stopping the switch from sticking.

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Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99


 - posted 08-10-2008 05:31 PM      Profile for Mark Gulbrandsen   Email Mark Gulbrandsen   Send New Private Message       Edit/Delete Post 
Troy,

Right on, I wasn't going to let Joe in on that secret though becuase he already knows everything! Thats called a snubber. The safest way to do it is to place a 10 ohm 1/2 watt resistor in series with the cap.... at least a .01 at 600 volt or greater ceramic disk type. If the cap happens to short out the resistor will burn up so the platter doesn't go into high speed payout. The cap acts to quench the spark (actually high frequency rf) that happens across the micro-switch contacts when they break contact.

Mark

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Joe Redifer
You need a beating today

Posts: 12859
From: Denver, Colorado
Registered: May 99


 - posted 08-10-2008 05:35 PM      Profile for Joe Redifer   Author's Homepage   Email Joe Redifer   Send New Private Message       Edit/Delete Post 
quote:
FWIW: The drive motors used on these platters are not stable enough to be able to use a linear feed control device like the phase control. They may work now but they will come back to haunt you in the near future!
2 things:

#1 - These were all originally phase control platters.

#2 - if they are not stable enough for "linear feed" then they would not be stable enough to be used as take-up since it has no choice to be, you know, linear.

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